Sensitivity training.

A secondary look at 3 prospective trials of intracranial proton therapy confirms pretty exquisite radiation sensitivities of the hypothalamus and pituitary at young ages. Among 189 pediatric patients prospectively followed after brain radiation, some hormone deficiency developed in over half by year 5. More specifically, in almost all those getting ≥40 Gy to 50% of the hypothalamus/pituitary and in almost none getting <20 Gy. Growth hormone deficiency was the most common (33%) followed by hypothyroidism (20%), with rates of all others in the single digits. | Vatner, J Clin Oncol 2018